Apparatus for the scouring of wet-spun filament bundles

ABSTRACT

A process for the scouring treatment of wet-spun continuous multifilament bundles wherein said bundles are arranged in a plurality of elongated and parallel fleece mat strips on a pervious endless belt, each of said strips having a thickness of at least 5mm and 100-1,000 crossings of multifilament bundles.

United States Patent 1191 Katsuyama et al.

Jan. 1, 1974 APPARATUS FOR THE SCOURING ()F WET-SPUN FILAMENT BUNDLESInventors: Shlgeo Katsuyama; Atsumi Asami;

Masahide Watanabe; Tsutomu Sato; Toshiaki Norimatsu; Eizo Nakajma, allof Miyazaki-ken, Japan Asahi Kasei Kogyo Kabushiki Kaisha, Osaka, JapanFiled: Feb. 25, 1972 Appl. No.1 229,384

Related U.S. Application Data Division of Ser. No. 881,345, Dec. 2,1969, Pat. No. 3,672,819.

Assignee:

Foreign Appliea tidn Priority Data Dec. 3, 1968 Japan ..43/88229 Feb.13, 1969 Japan ..44/102l2 "11's. Ci..1,....'.'.' 28/1 SM Int. Cl B08b3/00 Field of Search 28/1 SM; 8/137, 139.1

[56] References Cited UNITED STATES PATENTS 3,387,756 6/1968 Goodner28/1 SM 3,436,797 4/1969 Graf et a1. 28/1 SM 3,485,428 12/1969 Jackson28/1 SM 3,562,77] 2/1971 Fridrichsen 28/1 SM Primary Examiner-Louis K.Rimrodt [57] ABSTRACT A process for the scouring treatment of wet-spuncontinuous multifilament bundles wherein said bundles are arranged in aplurality of elongated and parallel fleece mat strips on a perviousendless belt, each of said strips having a thickness of at least 5mm and100-],000 crossings of multifilament bundles.

3 Claims, 8 Drawing Figures PAIENIEUJAN 1mm SHEEI 1 BF 4 FIG. IA

PATENTEB JAN I I974 SHEET 2 [IF 4 FIG. IB

FIG. 2B

PAIENIEUJAN H974 SHEET 3. BF 4 500'Wmin IA IOOO /mTn 8OOWm|n DENIERAPPARATUS FOR THE SCOURING OF WET-SPUN FILAMENT BUNDLES This is aDivision of application Ser. No. 881,345, filed Dec. 2, 1969, now US.Pat. No. 3,672,819 granted 6/27/72.

This invention relates to an improved process for the scouring ofwet-spun continuous filament bundles, at a high speed and in acontinuous way and an apparatus for carrying out the same.

The invention should be applied to fine filaments, each having a denierless than 10d, the overall denier of the filament bundle being limitedto less than 1,000 denier.

ln the following, the description will be directed, for thesimplification thereof, substantially to the case of the scouringtreatment of continuous regenerated filament bundles to which theprinciples of the invention may be most advantageously applied. Itshould be however easily understood from the whole description of thepresent specification to be set forth that the invention may be equallyapplied to other kind of wet-spun continuous filament bundles.

There is nowadays such an appreciable tendency that the rayonmanufacturing industry loses the game with the synthetic fiber industrywhich has taken an amazingly fast pace in its development. We havecarried out a considerable and profound investigation into thedevelopment of rayon manufacturing technique from all possible sidesthereof for keeping pace with the comparative synthetic fiber productiontechnique.

As in step of the investigation in the above sense, various problems incarrying out the scouring of continuous rayon filaments upon spinningformation thereof.

While otherwise disclosed in the literature, the scouring treatments ofspun rayon filaments are performed almost exclusively by relying uponthe cake scouring technique wherein the filament bundles in the shape ofa cake or cakes per 'se are subjected to the treatment. In this case,the filament mass will be disadvantageously and differently treated atvarious points thereof, indeed, by virtue of uneven and different modesof contact with the treating liquid, thereby inviting uneven andlocalized yarn characteristics of the finished products. ln order toobviate such conventional drawbacks, the continuous spinning process hasalready been proposed and carried into effect in'practical technique, inplace of the traditional cake bleaching process. A

It should be noted that the case of scouring treatment of continuouswet-spun filament bundles arranged in linear state, the speed oftreatment amounts generally to 100 m/min. or so, thus the economicalmerit of the process being too small to be accepted. For this reason, wehave devoted ourselves to develop an amazingly improved and continuouslyworkable process and apparatus for the scouring of continuous wet-spunfilament bundles for the realization of processing speed in the range ofSOD-1,000 m/min.

It is a commonly known to carry continuous filament bundles on anendless conveyor net for the continuous treatment of these bundles at ahigh operating speed. According to this prior technique the filamentbundles are placed in their zigzag shape on the conveyor net and varioustreating liquids are fed in several successive stages onto thetravelling filament bundles.

According to a similar prior proposal, continuous filament bundles aresuccessively supplied on a travelling conveyor so as to take each acombination of two or more kinds of curved or looped planeconfigurations having various plane sizes for subjecting them tosuecessive liquid treatments.

The filament bundles carried on the pervious conveyor belt takeaccording to the prior technique zigzag, rough loops or the like simplerforms and are stuck only two or three layers when seen at a certainpoint as a measuring reference.

Therefore, when it is desired to subject these stuck filament loops orthe like to a treatment such as bleaching, the required whole processingwill consume a considerably long period, thus the conveyor destined forthe carrier means being considerably long and the required floor spacebeing too large to be economically accepted, even when thecorrespondingly large investment capital for fitting the necessaryliquid or the liketreatment applicances be ignored. Therefore, it can beconcluded that this kind of improvement may be carried into effect onlywith poor economical and productive efficiency.

It is therefore the main object of the invention to provide a highlyimproved technique for the scouring treatment of wet-spun continuousfilament bundles continuously and at a high operating efficiency as highas at SOD-1,000 meters per minute.

A further object of the invention to provide an improved technique ofthe above kind for bleaching treatment of wet-spun continuous filamentbundles with a highly small requirement of floor space and at aconsiderably small operating cost.

The method according to this invention has its broadest coverage,residing, indeed, in a process for the scouring treatment of wet-spuncontinuous filament bundles, each of said filaments having 10 denier atthe maximum and each of said bundles having less than 2,000 denier, inthe shape of parallel bands on a pervious conveyor means, said processbeing characterized by that the band comprised of said filament bundleis in the shape of an elongated and thick fleece mat having a thicknessof at least 5mm and l00l,000 crossings of multifilament bundles whenmeasured at any point along the length of said band and in the state ofthe band of filament bundle as projected from a casting nozzle onto anddeposited in position on said conveyor means by means of water sprayjet.

For carryingout the said process in a more advantageous way, a pluralityof wet-spun continuous filament bundles is thrown onto the surface of atravelling endless and pervious conveyor means in a thickly stuckthree-dimensional band having a thickness larger than 5 mm by blown eachbundle through an air jet means, while at the same time a liquid jetstream is blown onto the stuck fibrous band in such a way that the airjet stream and the liquid jet stream cross at least partially with eachother on the conveyor means for practically setting the relativeposition of the blown-on fiber bundles constituting said band of thecontinuous filament bundle and then the band-shaped fiber stuck issubjected to bleaching on the conveyor band.

The apparatus adapted according to this invention for carrying out theabove process may comprise in combination, a hollow projecting cylindermeans arranged for receiving and delivering a continuous filamentbundle; an air ejector having its outlet end opening into the interiorspace of said projecting cylinder; a conveyor means of pervious naturefor receiving the projected filament bundle delivered together withejected air streams from said cylinder, said filament bundle beingshaped on the conveyor means into an elongated stuck of elongated fleecemat of filament bundles as the conveyor means proceeds; and a spraynozzle for provisional setting said fleece structure ofthree-dimensional nature having a thickness of at least 5 millimeters bymeans of water jet streams impinged on the fleece band as it is formedon said conveyor means.

In contrast to the above inventive concept as proposed for attaining theaforementioned objects, those skilled in the art have had such a thoughtthat when a multilayer of densely stuck fiber loop band ofthreedimensional nature consisting of several tens or even hundreds ofcomplexedly looped multifilament layers, having an overall thicknesslarger than 5 millimeters when specified in case of fine continuousfilaments less than l denier or so may result in frequent tanglings andbreakages when taken out at a high winding speed such as 500-l,000m/min. at the delivery end of the travelling carrier conveyor upon whichthe thickly stuck and densely condensed fleece fiber band is formed andmaintained throughout successive aftertreatment steps, thus having beendeemed as completely impractical.

In practice of the inventive process as proposed, it is important to setprovisionally and a lesser or greater fixed manner, the once formeddense and heavily thicker fleece band formation of the complexedlylooped multifilaments by virtue of the spraying water jet streams actingas a kind of most economical setting medium onto the conveyor meansthrough the whole thickness of the fiber fleece band formed under theutilization of the energy of air jet streams delivered from the outletor lowermost end of the projecting cylinder.

The term pervious" as used throughout the specification and appendedclaims means such nature of the conveyor or of the densely looped andstuck multifilament fleece band means that it allows passagetherethrough of air, water or the like liquid medium, or the both.

It would be conceivable that when the thick and densely loopedmultifilament fleece band having an overall thickness at least mm isformed, maintained and subjected to successive after-treatments, theresulted effects thereof can be uneven or subjected to appreciablemodification and alteration in the mutual position of the multifilamentloops caused by unintentional application of foreign forces in thecourse of travel of the conveyor means carrying the densely loopedfibrous band. According to our practical experimerits, however, it hasbeen found that there is substantially no fear of such troubles, thanksto the provisional setting of the mutual multifilament loop structure bymeans of water jet streams applied to the newly shaped multifilamentloops stuck below the delivery end of the projector cylinder, on the onehand, and to the highly pervious nature of the densely looped fleecemat, on the other hand.

In order to avoid fear of tangling and breakage of filament bundle inthe course of the winding operation after passage through the scouringand drying stages, it is most advantageous to provide a second conveyormeans with its receiving end placed in a lightly overlapped manner withand below the delivery end of the first conveyor means.

According to our practical experiments, the overall thickness of thedensely looped fleece mat band amounts at its upper limit to as large asabout 20 mm. This upper limit will be further increased under stillfurther improved operating conditions. Therefore, it would be easilyconceivable that the densely looped band seems practically as a kind offleece mat. It is highly advantageous to so arrange that the fleece bandis transferred in its up-and-down state from the first conveyor means tothe second conveyor means.

According to the process of the invention, it has been succeeded toarrange as many as band strips of condensed multifilament fleece mat ona pervious conveyor means of 2 meter width, practically there beingalmost no idle space between each two neighboring fleece bands. Sucharrangement provided a considerably high operation efficiency in thepractice of scouring of wet-spun multifilament bundles with acomparatively small floor space and with a possible minimum capitalinvestment.

These and further objects, features of the invention will become moreapparent as the description proceeds by reference to the accompanyingdrawings, in which:

FIGS. 1A and 18 represent a single figure in combination, thecoincidence line being shown at I I, which figure is a substantiallysectional side view of a preferred embodiment of the arrangement adaptedfor carrying out the process according to this invention.

FIGS. 2A and 28 represent in combination a single figure, thecoincidence line being shown at II II, which is a plan view of thearrangement shown in FIG. 1.

FIG. 3 is an enlarged sectional view of essential parts of the mechanismfor the formation of multifulament condensed fleece mat band, saidmechanism being a constituent of the arrangement shown in FIGS. 1-2.

FIG. 4 is a perspective view of a plurality of said mechanisms shown inFIG. 3.

FIG. 5 is a chart showing several examples of condensed multifilamentfleece mat band shown in its thickness in function of the denier ofmultifilament bundle.

FIG. 6 represents several preferred embodiments of scraper means.

Now referring to FIGS. 1-2, the numeral 10 denotes a wet-spun continuousfilament bundle, made preferably of regenerated cellulose, especiallyviscose rayon. This filament is supplied from a proper source, such asrayon cake, not shown. The multifilament 10 is supplied through feedroller 11 and guide 12 to a supply ejector 13, the introductory part ofwhich projects from a projector cylinder 14, while the main part and thedelivery end of ejector 13 are positioned within the interior of saidcylinder 14.

Compressed air is supplied to the ejector 13 from a supply source, notshown, through a feed piping 39 fitted with a regulator valve 38, thusthe multifilament bundle 10 being introduced by the suction effect. Theintroduced bundle 10 is delivered from the outlet or lowermost end ofthe ejector 13 together with the delivered air jet streams, saiddelivered bundle being projected substantially in a straight line at 49and impinging against the curved inside wall surface of the cylinder 14.The compressed air streams perform in this region swirling motion withinthe interior of said cylinder,

thereby the filament bundle being. transformed into a series ofcontinuous loops as shown especially in FIG. 3. In this way, filament.y'arn loops are continuously and successively projected onto the.surface of a travelling endless belt 17 from th'elowermost end of theprojector tube 14 under the influence of the downwardly issuing air jetstreams. This belt 17 is made ofa pervious material such as wire net orthe like.

Numeral 41 and 44 show supporting brackets which are fixedly mounted,although the fixing and mounting meanshave been omitted. from thedrawing, although not shown. For rigidly and stationarily positioningthe projector cylinder 14 together with the ejector 13 as shown, thereare provided fixing steel band strips 43 and 46 and fixing nut. means 42and 45.

Although in the foregoing, the multifilament fleece mat forming unitutilizing the air jet and the swirling motion thereof has been shown anddescribed in singular only, a plurality of such units or mechanisms arearranged in practice for a workable plant, as only schematically andpartially illustrated in FIG. 4. The number of such units may amount to100 or more. These units are generally arranged in line laterally of thepervious en'd belt 17. Under certain occasion, however, they arearranged in two or more rows and in some offset manner, although notillustrated.

The numeral 19 denotes a water supply pipe or distributor from whichwater is fed under pressure to the corresponding number of spray nozzles20. The water spray jet 22 delivered from the outlet end of each ofthenozzles 20 is projected against the newly formed multifilament fleecemat 21 as it is formed just below the projector tube 14 on the surfaceof said travelling belt 17. The nozzle 20 is so directed and arrangedthat the projected area of water jet onto the fleece mat as formedcrosses the air jet area projected against the conveyor belt 17. Byemploying this measure, the continuously projected monofilament loopsfrom the lower or outlet end of the projector cylinder 14 at a heavyspeed is avoided from being strongly disturbed and entangling which maybe caused by the rushingly discharged air jet streams t'rom theprojector cylinder and thus the looped multifllament can be accumulatedon the surface of the conveyor belt .17 without being flown off. Theshape of the multifllament loop is highly variable and may take the formof circles, ellipses, eights or even the shape of an almost overlappedslits. In this way, however, the multifilament loops are accumulated anddeposited on the surface of the travelling conveyor belt 17 in a thickand elongated fleece mat 21 having a thickness of 20 mm or more, as wasreferred to hereinbefore. Therefore, the water jets act as the mediumfor setting provisionally the mutual position of the condensedlydeposited multifllament fleece structure. The fleece mat 21 represents100 2,000 crossings of the multifilament when measured at a certainpoint downstream of the deposited area. When selecting properly thefeeding speed of the multifllament, the pressure and delivered quantityof the projecting compressed air and the travelling speed of theconveyor belt 17.

At the outlet end of the projector cylinder 14, a limiter made into theform of a channel is fixedly attached thereto by any conventional meanssuch as welding, said limiter acting so as to limit the width of theprojected fleece band 21 to a certain predetermined dimension such as 860 mm. Under certain operating conditions, however, this limiter can bedispensed with without prejudice. In the preferred embodiment shown inFIG. 4, the limiter consists of a series of limiter elements arranged ina lateral row and made into a single piece adapted for cooperation withthe multi-unit system. The vertical walls 63a of the limiter serve inpractice for the width limiting purpose.

The pervious conveyor belt 17 is dirven in the counter clockwisedirection when seen in FIGS. 1, 3 and 4, said belt being threaded forthis purpose around a drive roller 16 and a driven roller 18, althoughthe prime mover has been omitted from the drawing only for simplicity.

In the embodiment shown, the drive roller 16 is larger than the drivenroller 18 and arranged adjustable in its vertical position as hinted bya double headed arrow A.

When the travelling speed of the conveyor belt 17 is adjusted to 0.5 1.0m/min, as an example, and by selecting the bore of projector cylinder14, the blowing speed and pressure of the swirling compressed air toproper values, the elongated band strip of fleece mat 21 will representa thickness of 5-20 mm or more, a width of 8 60 mm and multifilamentcrossings 2,000. Thus, the fleece band strip 21 represents athreedimensional, highly condensed multilayer construction.

When the conveyor belt 17 turns over at the place of the follower roller18 so as to change the travelling direction from left to right in FIG.3, the wet fleece band strip 21 is transferred in its up-and-downreversed state onto the surface ofa second pervious conveyor belt 28,this fleece transfer being carried out without appreciable alteration ofthe general structure thereof, indeed, thanks to the provisional settingeffect provided by the application of the water jet streams. If thisapplication should not be adopted, the fleece structure could besubstantially damaged and thus considerable difficulty in entanglelessand smooth take-up of the multifilament would be encountered at thecombined final stage of the scouring and drying state to be describedfor winding up of the multifllament on a bobbin.

While the up-and-down reversed multifilament fleece band strip 21 isconveyed on the second pervious belt 28 from left to right in FIGS. l-3,it is more compacted by the pressure exerted from upper by the driveroller 16 and the depositing and setting effect will be furtheraccentuated. In this case, also, the contained water content in thefleece will provide an important roll in the prevention of theinintentional scattering of the compacted fleece construction. By thispressurizing operation, the preserving effect of the mutual fleececonstruction of the highly multitudinously crossed multifllament textureis substantially maintained when the fleece strip is subjected to ascouring operation on the second conveyor belt 28.

There are provided two distributor pipes 23 and 23' adapted forsupplying scouring liquor of known composition to a number of spraynozzles 24, 24' which shower the fleece layer strip with said liquor. Inthis way, the fleece strip 21 is subjected to an even scouring effect.The scouring spray streams are shown at 25. The thus treated fleecestrip is passed through two pairs of squeezing rollers 29, 30 and 29',30'.

The squeezed fleece layer strip is then conveyed by means of the secondconveyor 28 into a tunnel dryer 26 for being dried up. At this stage ofthe operation, the conveyor 28 is practically covered fully with a largenumber of the parallel fleece strips having a large thickness andsubstantially compacted structure, the drying thermal efficiency will behighly improved in comparison with the prior art.

In this respect, it should be noted that all the figures the interstripidle gaps were shown in a rather accentuated manner for avoiding anypossible confusion in the drawing, and the practical value amounts to avery small neglectable one.

The multifilament bundle, upon leaving from the outlet end of drier 26is taken out in the form ofa continuous line-shape as at 50 through ayarn guide 31 and for the purpose ofwinding-up on a bobbin, not shown.This winding-up operation can be effected at a high speed of 500 1,000m/min without fear of yarn tangling and breakage.

in FIG. 5, several examples of the multifilament fleece band stripprovided by the novel teaching, showing the preferred mutualrelationship among the specified data concerning denier ofmultifilament, thickness of fleece band strip and winding-up speed.These data were ascertained by our practical experiments. From thesedata, a highly improved scouring efficiency may well be supposed.

Upon checked the processed multifilaments, it was ascertained that thescouring and drying effects were highly even and superior. Thus, theoverall quality of the yarn could be substantially improved.

The supply roller 11 is rotatably mounted at its both ends by hearingmeans 32, 32. Bearing means 33, 33' are provided in the same way forconveyor drive roller 27, and those of 34, 34 for the follower roller18. Several bearing means 35, 35'; 36, 36; 37, 37'; 38, 38 are alsoprovided for drive roller 16, squeezing roller 30, 30' and conveyordrive roller 27', respectively.

Numeral 39 represents a conventional mechanism for the prevention offluctuation of travelling of conveyor means 28. The numeral 40represents several fans which deliver hot air to the drier 26.

In FIG. 6, several preferred embodiments of scraper means are shown at60a, 60b and 600. The first one at 600 consists of a rigid round barmade preferably of stainless steel. The second one at 60b consists ofplastic material such as semirigid bar having substantially arectangular cross-section. The third one shown at 60c comprises anelongated rigid bar-like base 61 embedded with brush hair 62.

One or more of these scraper means is/or arranged at an intermediateprotion between the ends of the second conveyor belt 28 and in physicalcontact with the lower surface of the upper travelling zone thereof.These scrapers are arranged laterally of the belt 28 in the similar wayas the rollers 29, 29'. During the scouring treatment. the liquid willfrequently fill the meshes of the conveyor net 28 or the like previouscarrier means. By the provision of these scraper means, the thus fillingliquor film can effectively-broken, thus a possible lateral flow of thescouring liquor on the surface of the belt being effectively avoided.

Several numerical examples of the process according to this inventionwill be given in the following for better understanding of theinvention. The results are shown in FIG. 5.

EXAMPLES The operation was carried out under the following conditions:

1. width of the projected and deposited multifilament fleece band strip:27 mm;

2. travelling speed of first conveyor belt: 0.5 m/min;

3. scouring period (length of scouring section: 7.5

m): 15 m/mm 4. drying-up period (length of drier section: 5.5 m):

l l min;

5. humidifying period (length of humidifier section:

5.9 m): 10 min.

When operated, the results concerning supply speed of the fedmultifilament, denier of the multifilament bundle and thickness of theprojected and deposited fleece mat strip were as shown in the followingTable I.

There is a certain prior art which recommends to use mechanicalrotatable means such as a rotatable disk formed with a yarn guideopening for supplying a looped yarn layer on a travelling endless belt.Use of such mechanical means would injure considerably the nature of theyarn if the latter comprises a finer multifilament of regeneratedcellulose than 10d per filament. According to this invention, suchdefect can well be avoided.

It will thus be seen that the scouring process and apparatus accordingto this invention will provide a substantial progress in the art.

TABLE I Filament 600 pp y Speed in m/min Stuck Density measured in mmDenier The embodiments of the invention in which as exclusive propertyor privilege is claimed are as follows:

1. An apparatus for depositing and shaping at least one wet-spuncontinuous multifilament bundle on a continuously movable perviousconveyor means comprising a hollow projecting cylinder means arrangedfor receiving and delivering a continuous multifilament bundle, an airejector having its outlet end opening into the interior space of saidprojecting cylinder, a first conveyor means of pervious nature forreceiving the projected multifilament bundle delivered together withejected air streams from said cylinder whereby said multifilament bundleis shaped on said first conveyor means into an elongated fleece matstructure as the conveyor means proceeds, a spray nozzle forprovisionally setting said fleece mat structure of three dimensionalnature havingthickness of at least 5 mm. by

3. An apparatus as set forth in claim 2 further comprising channel meansassociated with each cylinder means and having parallel spaced-apartside members extending in the direction of travel of said first conveyormeans to assist in forming said elongated fleece mat structures.

1. An apparatus for depositing and shaping at least one wet-spuncontinuous multifilament bundle on a continuously movable perviousconveyor means comprising a hollow projecting cylinder means arrangedfor receiving and delivering a continuous multifilament bundle, an airejector having its outlet end opening into the interior space of saidprojecting cylinder, a first conveyor means of pervious nature forreceiving the projected multifilament bundle delivered together withejected air streams from said cylinder whereby said multifilament bundleis shaped on said first conveyor means into an elongated fleece matstructure as the conveyor means proceeds, a spray nozzle forprovisionally setting said fleece mat structure of three dimensionalnature having a thickness of at least 5mm. by means of water jet streamsimpinged on the fleece band at the point where said structure is formedon said first conveyor means, and means for inverting and compressingsaid fleece mat structure including a second conveyor means dispOsedbeneath said first conveyor means, said first and second conveyor meansincluding first and second endless belts respectively having opposedruns disposed in closely spaced-apart relation running in the samedirection.
 2. An apparatus as set forth in claim 1 further comprising aplurality of cylinder means, air ejectors and spray nozzles disposedadjacent each other for forming a plurality of said elongated fleece matstructures on said first conveyor means in spaced-apart relation to eachother as said conveyor means proceeds.
 3. An apparatus as set forth inclaim 2 further comprising channel means associated with each cylindermeans and having parallel spaced-apart side members extending in thedirection of travel of said first conveyor means to assist in formingsaid elongated fleece mat structures.